I've been having an issue with my car shifting hard at times.. It'll get warmed up, start shifting hard, I'll pull over.. shut the car off.. wait about 30seconds, and drive off like it never happened.

I've been reading up on this issue, and it seems like a number of grand prix owners have had this exact issue. I've also read that a probable fix for the problem is the pressure control solenoid being replaced.

My question is... are any of you familiar with this problem I'm having, and did replacing the pressure control solenoid fix your problem?

I have heard of this issue before. If you can replace the solenoid without dropping out the transmission (not sure), then that would be the first logical thing to try. Also could try a fluid change, but you'll just be wasting the fluid if you end up doing any other work.

Yeah.. I already did the fluid/filter change. I was reading more on it today.. and some models with this trans take some pretty serious work to get to the solenoid.. gotta lower the tranny a bit, and take off the side casing or something.. I'm gonna have my car in pieces this weekend anyway, I might as well see about doing that while I'm at it..

Yep it's the solenoid. Happened to my grandma's 02 GT with only 35K on the clock. They had a hard time figuring out what it was because after the car was shut off the problem went away and wouldn't come back for a few weeks or months. Finally they brought it right in after it happened and it was the solenoid. $700 to get it replaced at the dealer and that's with the discount they give my grandpa. Don't know how much a new solenoid is or how much work it is to put a new one in but I guarantee you'll be happier doing it yourself instead of paying $700.

The solenoid is only $40.00.. I think there's 2 of them, though.. It could also be the valve body, but I think it's the solenoid. I'll have to look into it more. If anyone knows of a writeup on it, or a good source to find repair info on it I'd appreciate it. I have a friend that's a mechanic at a Toyota dealership, and he said I can have full access to a bay in the garage on any Saturday for nothing... I should be able to get it done myself if I can find some info on how to do it!

I'll be over at my grandparents tomorrow so I'll take a look at the service receipt to see exactly what they did to the car, hopefully that will be enough to help you out.

Sounds great, thanks!